In electronics, a switch is an electrical component which can connect or disconnect signals and communication paths between electrical devices. A switch is an important element in an integrated microelectronic system. Semiconductor switches are typically obtained through circuit design or microelectromechanical (MEM) design. U.S. Pat. No. 6,747,583 to Tucholski et al. describes a switch circuit comprising a compensating circuit with scaled current steering switches.
Due to their relatively low insertion loss and high isolation value at high frequencies, MEM switches are useful for controlling very high frequency lines, such as antenna feed lines and switches operating above 1 GHz. In U.S. Pat. No. 6,667,245 to Chow et al., a MEM switch is fabricated for integration into circuits utilizing typical CMOS processing steps. The MEM switch device made with these steps is readily integrable with other circuits.
However, the circuit design and MEM design both require extra steps to integrate the switching device with the microelectronic system. This will increase the overall fabrication cost of the microelectronic system. In addition, the switching device made through the circuit design or the MEM design also takes a significant chip area.
Accordingly, there exists a need for a switching device which occupies a small chip area in an integrated circuit and has low fabrication cost.